Science fiction author Neal Stephenson plays Halo on its hardest difficulty setting, Legendary, while using an elliptical exercise machine, the writer of Snow Crash told an audience in Austin today.

He tried the same thing with Rockstar's Western Red Dead Redemption, but it hasn't worked. Why would a man exercise like this?

"My relationship to games is slightly unusual," he said as part of his keynote address at GDC Online this morning. "I went into a serious binge-mdoe for a while on some Xbox games, mostly Halo, and began to notice that I would start playing it and suddenly it would be three in the morning, which wasn't that compatible with some of my other responsibilities in life. So I started to cut back. And I had another first-world problem that I needed to deal with, because I wasn't getting enough exercise.

"I just hated using things like treadmills and elliptical trainers because it's so tedious. And finally it occurred to me that I should just combine those two things [games and exercise]. So I actually built a rig that consists of an elliptical trainer with an Xbox 360 [attached]. I discovered that it's possible to balance the 360 controller on the yolk in the middle of the elliptical.

"I basically play Halo 3 in solo mode for 45-minutes stretches, a few times a week as a way to get aerobic stuff in.Halo 3 is probably the most crack-like game I've found; I don't have to learn anything new to play it. I'm trying to get through on Legendary. I'm maybe 2/3 of the way through. It goes very slowly, but that's what I want."

And why doesn't Rockstar's great game fit into his workout scheme? "I did play [Red Dead] on the elliptical some, but it was one of those games that required a lot of stopping and thinking, and that's bad for when you're trying to forget the fact that you're on an elliptical trainer."

Heed these fitness tips, dear readers. And, well, make sure you're getting a good enough workout if you're playing games at the same time.